"There is considerable damage within Grenfell Tower", he said. Hands cautioned that officials don't yet have exact details about the renovation that ended just a year ago.

"My understanding is that the cladding that was reported wasn't in accordance with United Kingdom building regulations", Hands told Sky News.

The fire at the 24-story public housing project broke out early Wednesday. The investigation will identify any criminal offence that has been committed.

Footage recorded from inside a fire engine making its way to the Grenfell Tower fire shows the shock and disbelief of firefighters as the scale of the blaze becomes apparent.

He said all records - including emails, minutes of meetings, correspondence with contractors, safety assessments, specifications and reports - must be kept intact.

"This is an incredibly distressing time for families and they have my commitment that we will do this as quickly as we possibly can", he said.

The number of the dead may change as investigations progress, police said. He has not provided details about the inquiry.

On Sunday, London Mayor Sadiq Khan acknowledged growing public anger surrounding the fire, saying it was a result of "mistakes and neglect".

Eleanor Kelly, chief executive of Southwark Council, on behalf of the newly established Grenfell Fire Response Team, said: "We want to make clear that whilst the emergency and local community response was nothing short of heroic, we know that the initial response was simply not good enough on the ground". More than 3 million pounds ($3.8 million) have been raised for the victims, and the British government has announced a 5 million-pound ($6.3 million) emergency fund. "This prime minister is not viable".

Residents who met Mrs May in Downing Street over the weekend said while they welcomed the funding they had not been consulted before the announcement was made.

"I would like to ask anyone who was in Grenfell Tower that night, but for whatever reason has not told us they are safe to please call our Casualty Bureau", he said. "Unfortunately they were not listened".

In addition, British health authorities will provide long-term bereavement counselling for those who lost loved ones in the tragedy. Counselors are already working with 52 families.

"The tragedy at Grenfell Tower has left a number of local people in need of urgent assistance", a spokesman for the three royals at Kensington Palace said.

There are another 43 social workers from across London who have started to help assess and support the affected families.

Scotland Yard on Monday confirmed at least 79 people perished in last week's blaze in west London but said it may not be possible to identify all the dead due to the intensity of the fire in the wealthy Kensington and Chelsea borough.